Bezafibratum
European Pharmacopoeia 7.0, 1490-1491. Requirements: Resolution factor (R) for bezafibratum and its impurity should be > 5.0.

Cefradine
European Pharmacopoeia 7.0, 1620-1622. Requirements: Resolution factor (R) for cefradine and cefalexin should be > 4.

Clindamycin hydrochloride
European Pharmacopoeia 7.0: 1716-1717. Requirements: the retention time of clindamycin hydrochloride is around 10 min.

Pioglitazone Hydrochloride
USP34-NF29, 3933. Requirements: the resolution factor between pioglitazone hydrochloride and benzophenone should be >15, and the tailing factor for the two compounds should both be <1.5 respectively.